The B lymphocyte surface antigen receptor membrane immunoglobulin has important functions in the binding and internalization of antigen, as well as in transducing signals through the plasma membrane which lead to cell activation, differentiation and apoptosis. Crosslinking of the receptor stimulates the Ras/Raf-1/MEK cascade with activation of p42.sup.erk2 MAPK and p90.sup.rsk. A second important B cell surface antigen receptor is CD40. CD40 is a 45-50 kD transmembrane glycoprotein expressed on all mature B cells. CD40 is a member of the TNF receptor family and has homology to the receptors for nerve growth factor, TNF-.alpha., Fas and CD30. The ligand for CD40 (CD40 L, gp39) is expressed on activated T lymphocytes and activation through CD40 plays an important role in T cell-dependent immunoglobulin isotype switching. The signal transduction pathways through CD40 are not well delineated.
Certain biological functions of a B lymphocyte (B cell) are tightly regulated by signal transduction pathways within B cells. Signal transduction pathways maintain the balanced steady state functioning of a cell. Disease states can arise when the steady state function of a cell becomes harmful to an animal. For example, allergic reactions occur due to undesired production of IgE antibodies specific for an antigen. In addition, autoimmunity can occur due to an animal mounting an undesired immune response against a self-antigen. Signal transduction pathways in a cell can be responsible for regulating cellular biological functions. As such, regulation of signal transduction pathways can assist in the regulation of undesired cellular biological functions.
Despite a long-felt need to understand and discover methods for regulating cells involved in various disease states, the complexity of signal transduction pathways has precluded the development of products and processes for regulating cellular function by manipulating signal transduction pathways in a cell. As such, there remains a need for products and processes that permit the implementation of predictable controls of signal transduction in cells, thus enabling the treatment of various diseases that are caused by undesired cellular function.